给一副扑克牌，求最长的顺子

#include<iostream>#include<vector>#include <set>#include <algorithm>using namespace std;using  std::random_shuffle;struct Recv{    int difference;    set<int>::iterator first;    set<int>::iterator last;};void Sort(int *arr, int len){    set<int>  myset(arr, arr + len);    Recv recv = { 0,myset.begin(),myset.begin() };    set<int>::iterator lt = myset.begin();    set<int>::iterator st = myset.begin();    if (st != myset.end() && (++st != myset.end()))    {        ;    }    int i = 1;    for (; st != myset.end(); )    {        if ((*st - i) == *lt)        {            st++;            i++;        }        else if (recv.difference < i)        {            recv.first = lt;            recv.last = st;            recv.difference = i;            i = 1;            lt = st;            st++;        }        else        {            i = 1;            lt = st;            st++;        }    }    for (set<int>::iterator mt = recv.first; mt != recv.last; ++mt)    {        cout << *mt << " ";    }    cout << "size=" << recv.difference << endl;    cout << endl;}template<class T>//强大的仿函数class display{public:    void operator()(const T& x)    {        cout << x << ' ';    }};void C(){    vector<int> ve;    for (int i = 0; i < 20; ++i)    {        ve.push_back(i);    }    for_each(ve.begin(),ve.end(),display<int>());    cout << endl;    random_shuffle(ve.begin(),ve.end());    for_each(ve.begin(), ve.end(), display<int>());}void main(){    //C();//忽略，只是为了练习一下random_shuffle函数    int arr[] = { 9,3,2,1,8,2,2,4,1,5,6,11};    int len = sizeof(arr) / sizeof(arr[0]);    Sort(arr, len);}